We're going to turn to the round-the-clock rush by u.P.S. And fedex to get the late christmas presents delivered. There has been fierce backlash from angry customers, blasting the two shipping giants. And we have the latest, now, from abc's alex perez in chicago. Alex, good morning to you. Reporter: Good morning, josh. We've been talking to a lot of people who have been coming here, trying to track down their packages. In many cases, they tell us the damage was already done. They didn't get their gifts when they wanted them most. This morning, a chorus of frustration from customers like debbie, who paid extra for guaranteed delivery of a new smartphone on christmas eve. But the gift didn't arrive until the day after christmas. I'm supposed to be out running errands and taking care of business. But I couldn't because I wanted to make sure I was there for the package. Reporter: Our own viewers, sounding off. U.P.S. Made my naughty list. Our package is in bethlehem, pennsylvania. Reporter: U.P.S. And fedex, which also saw some delays, blamed the delivery delays on what they call a perfect storm, bad weather, more packages and a shorter delivery season. While both companies have apologized to customers, neither say how many packages may have been affected. In san francisco, people were waiting in line at this u.P.S. Shipping center thursday before the doors opened. I just want to cry. My christmas presents are in that package. Reporter: Chetan says that 26% of shopping is online. It has a huge, profound impact on how they view the retailer, as well as the whole experience about buying online. Reporter: Companies are scrambling to make good on their guaranteed delivery promises. Amazon refunding shipping fees and throwing in $20 gift cards. Kohl's, paying for the items not delivered on time. And walmart, also ponying up gift cards. The union that represents u.P.S. Drivers says they're working as many hours as possible to get things back on track. And the good news is that both companies say they will keep working until every package is delivered. And u.P.S. Says they believe they are already pretty much caught up. Josh? Lara? That's good news. Yeah. Especially since christmas is only 363 days away.

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